package api

import (
	"log/slog"
	"net/http"

	"messenger/internal/auth"
	"messenger/internal/platform/config"
	"messenger/internal/realtime"
	"messenger/internal/store"
)

type apiHandler struct {
	store  *store.Store
	tokens *auth.TokenManager
	hub    *realtime.Hub
	log    *slog.Logger
	secure bool
}

// NewHandler builds the /api/v1 route tree with all middleware applied.
func NewHandler(st *store.Store, tm *auth.TokenManager, hub *realtime.Hub, log *slog.Logger, cfg *config.Config) http.Handler {
	h := &apiHandler{
		store:  st,
		tokens: tm,
		hub:    hub,
		log:    log,
		secure: cfg.Environment == "production",
	}

	mux := http.NewServeMux()
	authHandler := requireAuth(tm, http.HandlerFunc(h.websocket))

	mux.HandleFunc("GET /api/v1/ping", func(w http.ResponseWriter, r *http.Request) {
		writeJSON(w, http.StatusOK, map[string]string{"message": "pong"})
	})

	mux.HandleFunc("POST /api/v1/auth/register", h.register)
	mux.HandleFunc("POST /api/v1/auth/login", h.login)
	mux.HandleFunc("POST /api/v1/auth/refresh", h.refresh)
	mux.HandleFunc("POST /api/v1/auth/logout", h.logout)

	mux.Handle("GET /api/v1/users/me", requireAuth(tm, h.me))
	mux.Handle("GET /api/v1/users", requireAuth(tm, h.searchUsers))

	mux.Handle("GET /api/v1/contacts", requireAuth(tm, h.listContacts))
	mux.Handle("POST /api/v1/contacts", requireAuth(tm, h.addContact))
	mux.Handle("DELETE /api/v1/contacts/{user_id}", requireAuth(tm, h.removeContact))

	mux.Handle("GET /api/v1/conversations", requireAuth(tm, h.listConversations))
	mux.Handle("POST /api/v1/conversations", requireAuth(tm, h.createDM))
	mux.Handle("GET /api/v1/conversations/{id}/messages", requireAuth(tm, h.listMessages))
	mux.Handle("POST /api/v1/conversations/{id}/messages", requireAuth(tm, h.sendMessage))

	mux.Handle("GET /ws", authHandler)

	return mux
}

func (h *apiHandler) websocket(w http.ResponseWriter, r *http.Request) {
	userID, ok := userIDFrom(r.Context())
	if !ok {
		writeError(w, http.StatusUnauthorized, "unauthenticated")
		return
	}
	h.hub.HandleWS(w, r, userID)
}